A method for manufacturing a display device includes a first step of placing a substrate having a lower electrode formed thereon in a vacuum environment; a second step of forming in a vacuum an organic layer that includes a light emitting layer and covers the lower electrode; a third step of forming in a vacuum an upper electrode that covers the organic layer; a fourth step of forming in a vacuum a sealing layer that covers the upper electrode; and a cleaning step of cleaning the substrate after end of the first step before end of the fourth step.